Aaron Burr, a former U.S. vice president, is arrested in Alabama on charges of plotting to annex Spanish territory in Louisiana and Mexico to be used toward the establishment of an independent republic.

In November 1800, in an election conducted before presidential and vice-presidential candidates shared a single ticket, Thomas Jefferson and his running mate, Aaron Burr, defeated Federalist incumbent John Adams with 73 electoral votes each. The tie vote then went to the House to be decided, and Federalist Alexander Hamilton was instrumental in breaking the deadlock in Jefferson’s favor. Burr, because he finished second, became vice president.

During the next few years, President Jefferson grew apart from his vice president and did not support Burr’s renomination to a second term in 1804. A faction of the Federalists, who had found their fortunes drastically diminished after the ascendance of Jefferson, sought to enlist the disgruntled Burr into their party. However, Alexander Hamilton opposed such a move and was quoted by a New York newspaper saying that he “looked upon Mr. Burr to be a dangerous man, and one who ought not to be trusted with the reins of government.” The article also referred to occasions when Hamilton had expressed an even “more despicable opinion of Burr.” Burr demanded an apology, Hamilton refused, so Burr challenged his old political antagonist to a duel.

On July 11, 1804, the pair met at a remote spot in Weehawken, New Jersey. Hamilton, whose son was killed in a duel in 1801, deliberately fired into the air, but Burr fired with intent to kill. Hamilton, fatally wounded, died in New York City the next day. The questionable circumstances of Hamilton’s death effectively brought Burr’s political career to an end.

Fleeing to Virginia, he traveled to New Orleans after finishing his term as vice president and met with U.S. General James Wilkinson, who was an agent for the Spanish. The exact nature of what the two plotted is unknown, but speculation ranges from the establishment of an independent republic in the American Southwest to the seizure of territory in Spanish America for the same purpose.

In the fall of 1806, Burr led a group of well-armed colonists toward New Orleans, prompting an immediate investigation by U.S. authorities. General Wilkinson, in an effort to save himself, turned against Burr and sent dispatches to Washington accusing Burr of treason. On February 19, 1807, Burr was arrested in Alabama for alleged treason and sent to Richmond, Virginia, to be tried in a U.S. circuit court.

On September 1, 1807, he was acquitted on the grounds that, although he had conspired against the United States, he was not guilty of treason because he had not engaged in an “overt act,” a requirement of treason as specified by the U.S. Constitution. Nevertheless, public opinion condemned him as a traitor, and he spent several years in Europe before returning to New York and resuming his law practice.